I have 4-5 dozen brushes, and This one stands out as being one of my top (~3) favorites of all time. I suck at winged eyeliner on my hooded (in slightly different ways) eyes, which makes it So Freaking Difficult to make the wings match. I use this brush to cheat, using a soft shade of whatever shadow look I'm going for, as I can easily wipe the shadow line off to reset so I can try again before applying either eyeliner or just dark shadow over it. NOTHING compares to this brush. It is The most Thin and Precise one I have every found, But with quality bristles that don't hurt or irritate like other ones I've tried.
Even if you won't use it for the same weird reason I do, if you're looking for a brush of this nature, don't Waste your ?¸ on anything else. Not to mention, the way these brushes are made, they will last forever. Her brushes are a worthwhile investment. For the type of brush they are, they are an absolute Steal.